Pressure responsive material positioning devices



Jan- 31, 1957 J. A. GIBSON y 3,301,455

PRESSURE RESPONSIVE MATERIAL POSITIONING DEVICES n Filed March s, 1965 E s sheets-sheet 1 E www J. A. GIBSON Jan. 31,1196? IRESSURE RESPONSIVE MATERIAL POSITIONING DEVICES Filed March 8, 1965 I5 Sheets-Sheet 5 BY www United States Patent O1Y Claims priority, application Great Britain, Mar. 10, 1964, v

10,134/64 Claims. (Cl. 226-17) The present invention relates to devices for positioning articles and especially, but not sole'ly, articles in strip form.

A particular application of the invention is to the positioning of steel strip travelling along a support from eg. rolling mills or a guillotine, where the application of excessive force to the sides of the strip would cause buckling.y f

However, it is contemplated `that the invention has other applications. In particular, the invention may be applicable to an article in e.g. sheet form or even in the form of a series of separate articles.

According to the invention there is provided an articlepositioning device comprising a plurality of engagement members arranged each to engage the article so as to position the article in a desired position, and motor means arranged to position the engagement members in article-engaging posit-ions dependent upon at least one arbitrary dimension of the article.

In a presently preferred form of the invention, pairs of locator means such as rollers are moved into engagement with opposite sides of the strip, and a connection between them is locked to maintain the spacing between the rollers of each pair substantially constant. i The pairs of rollers are then acted upon whilst so llocked ,to .position the strip as desired. The force acting upon the rollers to posi'- tion the strip need not then be carefully controlled tov avoid buckling, since the spacing between the rollers is substantially constant owing to the locked connection 'between them,

The invention will be described by way of an example, reference being made to the accompanying drawings,

wherein:

FIGURE l is a schematic plan view of la positioning mechanism of a positioning device embodying the in vention for centralising steel strip leaving rolling mills, omitting the table along which the steel strip moves;

FIGURE 2 is a view in the direction of the arrow ll in FIGURE l with the jack for connecting the pair of 4locator rol-1ers removed;

FIGURE 3 is a section along the line III- lll of FIG- URE l, including the table; and

FIGURE 4 is a diagram of the hydraulic system of the device for operating the positioning mechanism.

The positioning mechanism shown in FIGURES 1 to 3 is arranged to position steel strip 10 (FIGURE 3) moving along a table 11 by means of locator rollers 12 which engage the sides of the strip,

Two -pairs of such locator rollers 12 are mounted, one pair in front of the other, on bell cranks 13 pivoted at 14 to permit the rollers to be moved into engagement with the sides of the strip.

Each pair of bell cranks 13 is connected lby a motor in the form of an hydraulic jack 15 (omitted from FIGURE 2) whereby the rollers 12 can be moved into and held in engagement with the sides of the strip, each jack 15 being pivoted on its respective cranks at 16.

A further hydraulic jack is arranged to act upon the Vbell cranks 13- to centralise the strip by means of crossheads 21 which are slidable on guide rods 22,

p 3,3%,455 Patented Jan. 3l, 1967 ice projections 23 on the crossheads engaging further rollers 24 on the bell cranks.

Initially the connecting devices 15 are fully extended, so that the rollers are spaced apart, and the jac-k 2) is fully retracted to permit freedom of movement of the cranks 13.

When the positioning devices are brought into operation, the jacks 15 retract until both their respective rollers 12 have been moved into engagement with the sides of the strip, which may or may not be central.

The resistance to further movement towards each other of the rollers 12 produces a slight rise in fluid pressure in the jacks 15, causing the jacks to be locked in a manner which will -be described later with reference to FIG- URE 4.

At this stage if, for example, the strip is oit centre towards the bottom of FIGURE 1, all four rollers 12 will 'be moved from the positions shown towards the positions 12a, the left--hand pair of cranks 13 rotating anticlockwise and the right-hand pair clockwise.

Further rise in ilu-id pressure operates valves to extend the jack 20, in a manner which will be described later with reference to FIGURE 4. Owing to the positionsof the four bell cranks, the first two cranks to be acted upon by the cross-pieces 21 are the upper two cranks, which are pivoted to move their respective rollers away from the strip. Their movement is transmitted through the locked jacks 15 to the lower cranks to move the lower rollers 12 towards the strip to centralise it.V

ings, the tendency of all four rollers 12 will be to move Y away from the strip, and buckling of the strip would therefore be avoided.

Taking another example, if the strip is skewed so as to lie above the centre-line at the right-hand end of FIG- URE l and below the centre-line at the left-hand end, after the jacks 15 have moved the rollers 12 into engagement with the strip the cross-heads 21 will act upon the lower right-hand crank (FIGURE l) instead of the upper right-hand crank as described previously, and upon the upper left-hand crank. The upper left-hand and lower right-hand rollers 12 will then move away from the strip and their respective cranks will act upon the other cranks 13 through they jacks 15 to straighten up or centralise the strip.l

Referring to FIGURE 4, the hydraulic system for operating the positioning mechanism of FIGURES 1 to 3 is provided with a three-position control valve 25 supplied by a pump 26.

To commence the centralising operation, the control valve 25 is moved to a right-hand position in which fluid is supplied from the pump 26 through a relief valve 27 and check valves 28 to the jacks 15. When the pressure builds up to about 5() p.s.i., check valves 29 open to allow the jacks 15 to retract, moving the locator rollers 12 (FIGURES l to 3) into engagement with the sides of the strip.

Engagement of the rollers with the strip sides checks further retraction of the jacks 15, so that the fluid pressure rises and, at about p.s.i. (when the load on the strip is about 50 lbs.), closes the relief valve 27 to lock the jacks 15 with the -rollers 12 in engagement with the strip sides.

A rise in the fluid pressure to about 250 p.s.i. opens -a valve 30 to supply fluid through a check valve 31 to the jack 20. A further rise of pressure to about 300 p.s.i.

J1 Opens a check valve 32 to commence extension of the jack 20 to centralise the strip l@ (FiGURE 3), the centralising force exerted by the jack 2t) being between 530 and 2,650 llbs.

When the strip is centralised, and the cross-pieces 21 (FIGURES l to 3) contact all four cranks 13, the jack 20 ceases further movement, and the resultant rise in uid pressure opens a relief valve 33 which by-passes the jack 2t) to waste.

The control valve 25 may then be moved to a left-hand position to extend the jacks and retract the jack 2t). With the control valve in this position, the pump supplies uid to the jacks 15 through the check valves 29 and to the jack through the check valve 32, the check valves opening at a pressure of about 50 p.s.i. Check valves 34 and 35 by-pass the valves 27 and 30 for this purpose.

When the jacks 15 are fully extended and the jack Ztl fully retracted, the control valve may be returned to a central position to connect the pump direct to waste.

If desired, the centralising operation may be commenced by the leading edge of the strip engaging a suitable device (not shown) on the positioning mechanism to move the valve 25 to its right-hand position.

The positioning device described above may be used in conjunction with a variety of machines such as welding machines, guillotines and coiling machines. Advantageously one such device may be placed in front of the guillotine and another such device behind the guillotine so that the strip may be accurately guillotined (i.e. either slit longitudinally or cut across) and then accurately positioned for further handling.

It is contemplated that a positioning device similar to that described above may be used for handling strip material other than steel strip, especially where the strip is liable to buckle, but not necessarily so.

I claim:

1. An article-positioning device comprising: support means; a plurality of engagement members movably mounted on said support means and movable into engagement with an article, for moving the article; first motor means acting upon said engagement members to move said members into engagement with said article; detection means for detecting an arbitrary dimension of the article; control means responsive to said detection means to maintain said engagement members in a selected relationship limiting the pressure exerted by the engagement members on said article; and second motor means acting upon said engagement members maintained in the selected relationship to move the article to a desired position.

2. An article-positioning device comprising: support means; a pair of engagement members movably mounted on said support means and respectively movable into engagement with opposite sides of an article, for moving the article; iirst motor means acting between said pair of engagement members to move said members into engagement with said article; detection means for detecting an arbitrary dimension of the article between the points of engagement by said engagement members; control means responsive to said detection means to maintain said engagement members in a selected relationship limiting the pressure exerted by the engagement members on said article; and second motor means acting upon said engagement members maintained in the selected relationship to move the article to a desired position.

3. An article-positioning device comprising: support means; two pairs of engagement members movable mounted on said support means and movable into engagement with an article for moving the article, each individual pair of members being engageable with opposite sides of the article; first and second motor means acting between the respective pairs of said engagement members to move said members into engagement with said article; detection means for detecting two arbitrary dimensions of the article between the points of engagement with the article of the individual pairs of engagement members; control means responsive to said detection means to maintain each individual pair of engagement members in a selected relationship limiting the pressure exerted by the engagement members on said article; and third motor means acting between the two pairs of engagement members maintained in said selected relationship to move the article to a desired position.

4, A device for positioning an article, comprising: a support structure; two pairs of engagement members, each pair of engagement members comprising two two-arm levers pivoted on said support structure and two roller means mounted on a iirst arm of each of said levers, said levers being pivotable to bring the roller means on each individual pair of levers into engagement with opposite sides of an article for moving the article, said iirst arms of each pair of levers extending away from the other pair of levers and the second arms of each individual pair of levers extending toward each other; first and second motor means acting between the respective pairs of levers to move said roller means into engagement with said article; pressuredetector means for detecting the pressures exerted on said article by said roller means; control means responsive to said pressure-detector means to lock said first and second motor means upon preselected pressures being exerted by said roller means upon said article; and third motor means acting between said second arms of one pair of levers and said second arms of the other pair of levers to move said article to a desired position.

5. A device as claimed in claim 4, wherein each of said iirst, second and third motor means is an hydraulic pistonin-cylinder device and said pressure-detector means is adapted to detect the pressures in the cylinders of said first and second motor means.

References Cited by the Examiner UNITED STATES PATENTS 4/1940 Redderv et a1 t- 242-76 x 9/1961 Nitkiewicz 226-199 X 

1. AN ARTICLE-POSITIONING DEVICE COMPRISING: SUPPORT MEANS; A PLURALITY OF ENGAGEMENT MEMBERS MOVABLY MOUNTED ON SAID SUPPORT MEANS AND MOVABLE INTO ENGAGEMENT WITH AN ARTICLE, FOR MOVING THE ARTICLE; FIRST MOTOR MEANS ACTING UPON SAID ENGAGEMENT MEMBERS TO MOVE SAID MEMBERS INTO ENGAGEMENT WITH SAID ARTICLE; DETECTION MEANS FOR DETECTING AN ARBITRARY DIMENSION OF THE ARTICLE; CONTROL MEANS RESPONSIVE TO SAID DETECTION MEANS TO MAINTAIN SAID ENGAGEMENT MEMBERS IN A SELECTED RELATIONSHIP LIMITING THE PRESSURE EXERTED BY THE ENGAGEMENT MEMBERS ON SAID ARTICLE; AND SECOND MOTOR MEANS ACTING UPON SAID ENGAGEMENT MEMBERS MAINTAINED IN THE SELECTED RELATIONSHIP TO MOVE THE ARTICLE TO A DESIRED POSITION. 